Title : Burden of invasive group B streptococcus infection among infants less than 90-day old in Oman: A multicentre study
Aim of study:
Group B streptococcus (GBS) is a leading cause of invasive infection among neonates and infants worldwide, with two described syndromes, early onset GBS (EOGBS) disease and late onset GBS (LOGBS) disease. In our study, we investigated the incidence of invasive GBS disease among infants less than 90-day-old in three tertiary hospitals in Oman and described their risk factors, clinical presentations, and clinical outcome.
We retrospectively collected data of less than 90-day-old Omani infants with culture-positive GBS from sterile samples from three tertiary hospitals in Oman (RH, SQUH and KH) from 2009 to 2018. Their clinical data was reviewed to identify risk factors, clinical presentations, complications during admission, neurodevelopmental sequelae, and clinical outcome. The data was analysed using SPSS version 23.0 and P-value of less than 0.05 was taken as significant. The incidence was calculated per 1000 live births.
Over 10 years, we identified 92 cases of culture-confirmed invasive GBS infection from 178,285 live births in the study-hospitals, giving the overall incidence of 0.53 per 1000 live births (95% CI 0.4 to 0.7). Of those, 64.1% (n=59) had EOGBS disease and 35.9% (n=33) had LOGBS disease. The annual incidence of invasive GBS disease was significantly higher in the last five years from 2009 to 2013 (0.69 per 1000 live births, 95% CI 0.5-0.9) compared to the previous years from 2014 to 2018 (0.69 per 1000 live births, 95% CI 0.5-0.9), (P=0.004). A significant increase in annual incidence of invasive GBS disease was observed over the study period. Infants in the LOGBS disease group had a higher risk of meningitis compared to EOGBS disease group (30.3% vs 10.2%, P=0.021). The mortality rate was 13.5% and of the remaining survived infants, only 43 infants were followed up. About 12% of them developed neurodevelopmental impairment following invasive GBS disease.
The incidence of invasive GBS disease in Oman is similar to what was reported worldwide, however the burden of the disease in terms of complications and mortality is high. In addition to that, a significant increase in annual incidence of invasive GBS disease in Omani infants was found over the study period. Therefore, measures to prevent perinatal transmission need to be emphasized and implemented. Further studies considering the potential benefit of universal culture-based screening of pregnant women on the burden of invasive GBS disease in Oman is needed, and studies considering serotypes and maternal vaccination needs are recommended.
Audience take away:
• The burden of neonatal invasive GBS disease.
• Measures to prevent perinatal transmission of GBS.